import { Bell, Check, Crown, FileText, MessageCircle, Star, Trophy, Users, type LucideIcon } from 'lucide-react';
import { api, type NotificationItem } from '@/api';
import { useAppData } from '@/state/AppData';
import { useAsync } from '@/lib/useAsync';
import { useToast } from '@/components/Toast';
import { EmptyState, ErrorState, LoadingState, Screen, ScreenHeader } from '@/components/ui';
import { relativeTime, toFa } from '@/lib/format';
import { MathText } from '@/lib/MathText';

const STYLE: Record<string, { icon: LucideIcon; color: string; bg: string }> = {
  xp_earned: { icon: Star, color: '#E8A400', bg: '#FFF8E1' },
  lesson_completed: { icon: Check, color: '#5FBF8F', bg: '#EAF8F0' },
  node_completed: { icon: Trophy, color: '#FF7A3D', bg: '#FFF1E6' },
  order_paid: { icon: Crown, color: '#9B7BFF', bg: '#F5F1FF' },
  ticket_replied: { icon: MessageCircle, color: '#4C5FD5', bg: '#EEF1FF' },
  family_link_accepted: { icon: Users, color: '#FF7A3D', bg: '#FFF1E6' },
  weekly_report_ready: { icon: FileText, color: '#91ADC6', bg: '#EAF2F6' },
};
const styleOf = (type: string) => STYLE[type] ?? { icon: Bell, color: '#9e9ec0', bg: '#f0eeff' };

export function NotificationsScreen() {
  const { setUnreadCount } = useAppData();
  const toast = useToast();
  const list = useAsync(async () => {
    const r = await api.notifications.list();
    setUnreadCount(r.unreadCount);
    return r.items;
  }, []);
  const items = list.data ?? [];
  const unread = items.filter((n) => !n.isRead).length;

  const markLocal = (predicate: (n: NotificationItem) => boolean) => {
    list.setData((prev) => prev?.map((n) => (predicate(n) ? { ...n, isRead: true } : n)));
  };

  async function markOne(n: NotificationItem) {
    if (n.isRead) return;
    markLocal((x) => x.id === n.id);
    setUnreadCount(Math.max(0, unread - 1));
    api.notifications.markRead(n.id).catch(() => {});
  }

  async function markAll() {
    markLocal(() => true);
    setUnreadCount(0);
    try {
      await api.notifications.markAllRead();
    } catch {
      toast('ثبت نشد؛ دوباره امتحان کن', 'error');
      list.reload();
    }
  }

  return (
    <Screen>
      <ScreenHeader title="اعلان‌ها" color="#4C5FD5" back mascot={{ char: 'sigma', mood: 'idle', size: 54 }}>
        {unread > 0 && (
          <button type="button" onClick={() => void markAll()} className="mt-3 rounded-full bg-white/15 px-3 py-1.5 text-xs font-bold">
            همه خوانده شد
          </button>
        )}
      </ScreenHeader>
      <div className="flex-1 overflow-y-auto px-4 py-4">
        {list.loading ? (
          <LoadingState text="دارم اعلان‌ها رو میارم…" />
        ) : list.error ? (
          <ErrorState error={list.error} onRetry={list.reload} />
        ) : items.length === 0 ? (
          <EmptyState text="فعلاً خبری نیست" />
        ) : (
          <ul className="flex flex-col gap-2">
            {items.map((n) => {
              const s = styleOf(n.type);
              const Icon = s.icon;
              return (
                <li key={n.id}>
                  <button
                    type="button"
                    onClick={() => void markOne(n)}
                    className={`flex w-full items-start gap-3 rounded-2xl p-3.5 text-right ${n.isRead ? 'border border-line bg-white' : 'border border-indigo/20 bg-[#EEF1FF]'}`}
                  >
                    <span className="flex h-10 w-10 flex-shrink-0 items-center justify-center rounded-full" style={{ backgroundColor: s.bg }}>
                      <Icon size={18} style={{ color: s.color }} />
                    </span>
                    <span className="min-w-0 flex-1">
                      <span className={`block text-sm ${n.isRead ? 'text-muted' : 'font-bold text-ink'}`}>{n.title}</span>
                      {n.body && <span className="mt-0.5 block whitespace-pre-line text-xs leading-6 text-body"><MathText text={toFa(n.body)} /></span>}
                      <span className="mt-1 block text-[10px] text-faint">{relativeTime(n.createdAt)}</span>
                    </span>
                    {!n.isRead && <span className="mt-1.5 h-2 w-2 flex-shrink-0 rounded-full bg-coral" />}
                  </button>
                </li>
              );
            })}
          </ul>
        )}
      </div>
    </Screen>
  );
}